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    <script>
        var arr = [1,2,3,4,5,6,7,8,9,10,11];
        var sum = 0;
        var k = 0
        function fn1(){
            for(var i=0;i<arr.length;i++){
                if(i%2!=0){
                    sum += arr[i]
                    k++;
                }
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            return sum/k;
        }
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